A method for determining simultaneously from an oxidized black liquor sample an amount of sulfide, an amount of total dissolved solids, and an amount of effective alkali present in the sample, wherein the sulfide amount, the total dissolved solids amount, and the effective alkali amount are determined by subjecting the sample to attenuated total reflection (ATR) ultraviolet/visible (UV/V) spectroscopy over a wavelength of from about 190 to about 500 nm. Data from analyzing oxidized black liquor samples, and from analyzing one or more black liquor samples which may be subjected to black oxidation, may be used in a black liquor oxidation (BLOX) system for monitoring and/or controlling sulfur emissions from a kraft process.